How your neighborhood can affect your health: A real-life experiment from Sweden

Imagine arriving in a new country, belongings on your back, and being randomly assigned to live in a neighborhood. Perhaps, using San Francisco Bay Area examples, your new home is East Palo Alto, a city long plagued by crime and poverty. Or maybe you are whisked to Woodside, where your neighbors have horses and collections of Teslas.

That random assignment, which actually occurred to refugees who arrived in Sweden between 1987 and 1991, could have a major impact on your health, particularly, according to a new study, your likelihood of developing Type 2 diabetes.

Three decades later, a research team from the Stanford School of Medicine, UC-San Francisco and Lund University, in Sweden, used this natural experiment to look at the effects of neighborhood quality on diabetes risk in a study published April 27 in The Lancet Diabetes & Endocrinology.

In this study, the researchers found that refugees assigned to housing in deprived neighborhoods had a 15 to 30 percent higher chance of developing Type 2 diabetes than counterparts assigned to less-deprived areas. These data were culled from records of 61,386 immigrants, ages 25 to 50.

This study was possible because the Swedish health-care system tracks in-depth data on all patients. So why did the neighborhood have such a strong effect? Co-author Rita Hamad, MD, explains:

We’re still working on this analysis, but we hypothesize that deprived neighborhoods make it harder for residents to access healthy foods and good health care. There may be fewer opportunities for education and employment, making it harder for them to purchase quality food and health care. And the chronic stress associated with living in a high-poverty or high-crime area might contribute to the onset of diabetes.

Hamad also shares some thoughts about lessons policymakers can take away from the analysis:

Our data suggest that decisions affecting the settlement and integration of immigrants can have long-term consequences for the health of the new arrivals, and that these societies may end up paying the price decades later if refugees don’t receive adequate support upfront.

This intriguing study has already generated media attention. For a compelling take, check out this piece from STAT News.